Whenever a star emerge, people are going to get excited, no matter what sport. When Norway won silver medal in fencing in the London Olympics, everyone suddenly loved fencing. Then Magnus Carlsen became the best chess player in the world, and all of a sudden everyone in Norway love chess. If either Messi or Ronaldo were American, I have absolutely no doubt that it would get Americans to like football.
In short, all countries love winners, and there's just no way the Americans would have the best player in the biggest sport in the world and not care about it.
